Björn Rust (he/him) is a post-industrial designer cum researcher, innovator and educator, developing context-sensitive innovation practices for people, planet and beyond.

Recent writings

  1. Opportunity hoarding
  2. Doing away with bullshit
  3. The course of my life, so far

A case for cognitive strain

The human brain is as amazing as it is fallible; our ideologies blind us and our experiences bias our behaviour. Most are now coming to understand these vulnerabilities, but just to what extent the brain can arrive at flawed conclusions is still widely unappreciated.

One of the most interesting models of the human brain is described by Nobel laureate Daniel Kahneman in his book Thinking, Fast and Slow. The book summarises an exhaustive body of work dating back to the early 1970s, developed in large part with fellow physiologist Amos Tversky. This model describes two systems, one fast (System 1) and the other slow (System 2).

The two systems are deeply entwined. The first relies on association to arrive automatically and effortlessly at an approximation of reality, which the second deliberately builds upon to present rational judgements. But this deliberateness comes at a price—System 2 can become overwhelmed and tires easily.

Perhaps this is why we celebrate intuitive design solutions. Intuition is in the domain of the fast and effortless System 1. The cogitative ease felt while using a truly intuitive product is a pleasure, however, less desirably, it also promotes casual and superficial thinking. By contrast, if a product requires a user to invest more effort, hereby engaging System 2 they are likely to make fewer errors. This effect is illustrated in a study of Princeton students as Kahneman recalls it.

The experimenters recruited 40 Princeton students to take the CRT. Half of them saw the puzzles in a small font in washed-out gray print. The puzzles were legible, but the font induced cognitive strain. The results tell a clear story: 90% of the students who saw the CRT in normal font made at least one mistake in the test, but the proportion dropped to 35% when the font was barely legible. You read this correctly: performance was better with the bad font. Cognitive strain, whatever its source, mobilizes System 2, which is more likely to reject the intuitive answer suggested by System 1.

This finding could make a case for products which promote cognitive stain where absolute precision is required, providing that the risk of fatigue is not too great. Perhaps if we challenged each other with more straining solutions, dispensing with the trend toward oversimplified products, we might raise to the challenge and grow towards a more considered, personally responsible mindset.

Inspired by: Thinking, Fast and Slow


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